The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Referring now to FIG. 1, an oscillator 102 outputs a sine wave to an inverter 104. The oscillator 102 may include a crystal oscillator or an oscillator having an LC resonance circuit, where the L refers to inductance and the C refers to capacitance. Although the oscillator 102 outputs a sine wave, many circuits require a square wave.
For example, a circuit 106 may operate based on a square wave clock signal output from the inverter 104. In order to produce the square wave clock signal, the sine wave input to the inverter 104 is increased in amplitude. When driven with a small sinusoidal input, the inverter 104 outputs a sinusoidal output signal. As the input sinusoidal signal gets larger in amplitude, the inverter 104 eventually saturates, outputting a signal more closely resembling a square wave.
As the input sinusoidal signal gets larger, the inherent noise of the inverter 104 becomes less significant in proportion to the input signal. The larger input sinusoidal signal, however, requires that the oscillator 102 have greater voltage headroom. Power dissipation also increases as the input sinusoidal signal gets larger. Further, at some point, the input sinusoidal signal may exceed limits of the inverter 104. For example only, breakdown voltages of components of the inverter 104 may be exceeded, which may result in unpredictable behavior and/or damage to the inverter 104.